^ 333 .) 
A'RCTIUM * *. 
Linn. Class §• Order. Syngene'sia f, Polyga'mia,./Equalis+. 
Natural Older. Compo'sita:§, tribe, Cynarocephal.e, Juss. 
— Lindl. Syn. pp. 140 & 152 ; Introd. to Nat. Syst. of Bot. pp. 197 
and 200. — Mack. FI. Hibern. pp. 142 & 154. — Hook. Brit. FI. (4th 
edit.) p. 410. — Compo'sitas; subord. Cardua'ce.e ; Loud. Hort. 
Brit. pp. 520 & 521. — Synanthe're.e ; tribe, Cynarocepiialaj ; 
Rich, by Macgilliv. pp. 454 & 455. — Cinarocf.phala:, sect. 1. 
Juss. Gen. PI. pp. 171 & 172. — Srn. Gram, of Bot. p. 121. ; Engl. 
FI. v. iii. p. 334. — Syringales ; type, Cynaraceae ; Burn. .Outl. 
of Bot. pp. 900 & 931. — CoMPo'snvE, Linn. 
Gen. Char. Involucrum ( common calyx ) (see figs. 1 & 5.) 
globose, imbricated, of numerous, spear-shaped, tapering scales, 
each with an incurved hook at the extremity (see fig. 6.), perma- 
nent. Corolla compound, uniform ; florets (fig. 2.) numerous, all 
perfect, equal, tubular ; the tube very long and slender; limb wider, 
egg-shaped, in 5 strap-shaped, regular, spreading segments. Fila- 
ments (see fig. 3.) 5, from the tube, hair-like, short. Anthers in a 
cylindrical, 5-toothed tube, as long as the florets. Germen oblong, 
downy at the summit. Style (see fig. 2.) thread-shaped, longer 
than the stamens. Stigmas 2, reflexed. Seed-vessel none, except 
the permanent closed calyx, falling off entire. Seed (fig. 4.) 1 to 
each floret, inversely pyramidal, with 4 unequal blunt angles, 
abrupt. Pappus (see fig. 4.) a tuft of simple rough bristles, shorter 
than the seed. Receptacle (see figs. 1 & 5.) flat, covered with nar- 
row, strap-shaped, chaffy scales, nearly as long as the calyx. 
The globose involucrum of numerous scales, with an incurved 
hook at their extremity ; the chaffy receptacle ; and the short, 
simple pappus; will distinguish this from other genera, with a 
capitate corolla formed of all tubular florets, in the same class 
and order. 
Two species British. 
A'RCTIUM LAPPA. Common Burdock. Clot-burr. Great- 
burr. Hurr-burr. 
Spec. Char. Leaves stalked, heart-shaped, wavy, without 
prickles. Involucrum when in seed nearly smooth. 
Engl. Bot. t. 1228. — Curt. FI. Lond. t. 238. — Woodv. Med. Bot. v. i. p. 41. t. 
15. — Linn. Sp. PI. p. 1143. excl. var. 3. — Huds. FI. Angl. (2nd edit.) p. 348, in 
part. — Willd. Sp. PI. v. iii. pt. III. p. 1631. — Sm. FI. Brit. v. ii. p. 844 ; Engl. FI. 
v. iii. p. 380. — With. (7th ed. ) v. iii. p. 905. — Hook. Brit. FI. p. 349, excl. var. 3 - — 
Light. FI. Scot. v. i. p. 445. — Sibtli. Fl. Oxon. p. 243. — Abbot’s FI. Bed. p. I74. — 
Thornton’s Fam. Herb. p. 678, with a figure. — Davies’ Welsh Bot. p. 75. — 
Burton’s Midi. Fl. v. ii. p. 377. — Iielhan’s Fl. Cant. (3rd edit.) p. 327. — 
Hook. Fl. Scot. p. 235, excl. var. [3. — Uvev. Fl. Edin, p. 171. — Fl. Devon, pp. 
Fig. 1. Vertical section of the Involucrum and Receptacle, in an early state. — 
Fig. 2. A Floret. — Fig. 3. Stamens, magnified. — F’ig. 4. A Seed. — Fig. 5. Verti- 
cal section of the Involucrum, and Receptacle, in a more advanced state than Fig. 1. 
— Fig. 6. Two Scales of the Involucrum. 
• From arktos, Gr. a bear ; from the coarse texture of the involucrum. 
+ See folio 91, n. t. $ See folio 147, n, f. } See folio 27, a. 
